The present invention generally relates to blood collection systems and methods of blood collection and, more particularly, it relates to autologous blood recovery systems, methods of blood recovery and blood transfer, and blood collection reservoirs, wherein blood recovery receptacles connected to a suction source can simultaneously collect and release blood.
There have been introduced into the marketplace a number of direct whole blood cardiotomy reservoirs and methods for using reservoirs during the recovery and collection of blood for subsequent reinfusion into a patient. Typically, a system might utilize a negative pressure source for blood delivery and collection in a reservoir and use the force of gravity for return of the collected blood to the patient. Alternatively, instead of using gravity, a roller pump or an intravenous pump might be used for reinfusion of blood collected to increase the rate of blood return to the patient. In each system, the blood collection reservoir cannot be used to simultaneously collect blood using negative pressure and reinfuse the blood using positive pressure, gravity or pressure above atmospheric.
Other autotransfusion systems in the marketplace incorporate disposable flexible liners in either blood collection or blood transfer reservoirs. In one instance, during blood collection, a negative pressure source is used to convey blood to the collection reservoir and thereafter the collected blood is transferred to a second liner reservoir for gravity feed return to the patient. If desired, the second liner reservoir can be subjected to external pressurization, internal pressurization cannot be utilized because of liner flexibility, to enhance the rate of blood reinfusion. As before, this type of system is not capable of simultaneously drawing and reinfusing blood. An additional disadvantage of this type system is that suction in the surgical field can be interrupted during liner changes.
Another marketplace liner system employs a liner reservoir in a single used hard plastic housing. The system utilizes negative pressure to convey blood from the operative field into the liner. When the liner is full, another unit is used. The first liner reservoir is then removed for blood processing or for reinfusion directly into the patient. Reinfusion may be achieved utilizing gravity or the rigid housing may be pressurized to accelerate reinfusion. As with the foregoing systems, this system is not capable of simultaneous blood collection and blood reinfusion. Also, the liner reservoir is a single use disposable item.
The liner reservoir systems have not been entirely satisfactory in the blood collection field. The systems have a long history of liner leaks and failure to adequately serve the surgical community. Additionally, the systems are labor intensive and difficult to handle when not routinely used.
The primary objective of the present invention is to advance the art field of surgical autologous blood recovery by providing a unique blood collection reservoir for use in intraoperative blood recovery systems. A characteristic feature of the collection reservoir, which is not found in the aforementioned systems devices, is its capability of maintaining a continuous predetermined suction while emptying the contents just previously collected in the reservoir. The simultaneous fill and draw property of the present reservoir cannot be found in existing blood collection reservoirs. Also, the reservoir eliminates the attendant disadvantages previously noted with respect to known systems reservoirs (leaking, suction interruption, pressurization, single use) and presents a simple, uncomplicated, multi compartment device which is easy to manufacture and use. Accordingly, we have invented an improved blood collection reservoir and system uniquely capable of simultaneously achieving an uninterrupted flow of blood into the reservoir for collection while releasing collected blood from the reservoir for processing or reinfusions.